Method and apparatus for thawing frozen fuel



Jan. 21, 1941. v ADAM ammo AND Armnnu FOR-THAWING rlgozu wan File d Oct.22, 19:57

INVENTOR. .Henryfiangs; )1 BY y M ATTORNEY Patented Jan. 21, 1941 UNITEDSTATES PATENT OFFICE METHOD AND APPARATUS FOR THAWING FROZEN FUEL 25Claims.

The present invention relates to an improvement in a method of thawingfrozen coal and an improvement in frozen coal thawing devices such asmay be used, in winter, to thaw out piles of 6 exposed commerciallysized coal or coke, in piles, or in coal carrying cars, wherein the coalhas been exposed to the weather and becomes so frozen as to prevent itsremoval or transfer from the piles or from the transport means.

In present practice, one method of thawing frozen coal is to insertsteam nozzles deep into the body of the frozen coal, and then force livesteam into the interior of the frozen pile of coal at about 150 lbs.pressure, until it is thawed out. While this practice is effective, itis extremely expensive, as vast volumes of steam are used, and theprocess of thawing the coal under this practice is slow.

In coal thus exposed any length of time to the winter weather, in piles,or in the transporting coal cars, it becomes stratified in its frozencondition, due to alternate weather thaws and freezing, so that,eventually the bottom portion of the coal in the pile or in the cars,being protected by the overlying coal from weather thaws becomessubstantially a solid frozen body, and the interlying strata of thecoal, between the eX- posed top layers and the solid frozen bottom layerbecomes more frozen, into different degrees of solidity, gradually, frombottom to the exposed top. Each weather thaw tends to thaw the toplayers and the water seeps down to the under layers and is there held toagain freeze, until eventually, the coal becomes a solidly frozen mass,

the bottom layers of which are always more solidly frozen than the upperand top layers.

Live steam at 150 lbs. pressure has a temper ature of approximately358.2 E, and has a humidity or moisture content of about 30 to per- 40cent. Steam under the above condition admitted to the coal pile, aspreviously noted, and as has been discovered, does not quickly noreconomically thaw the coal, as, due to its high pressure vast volumes ofthe steam quickly thaws its way out and is lost to atmosphere longbefore its latent heat becomes useful.

It has been discovered, and this discovery forms the subject matter ofthe present application, that an increase of humidity in the steam, in ahigher proportion than may be obtained in live steam from a boiler,greatly increases the speed of thawing the coal, and greatly reduces theexpense, because, as has been found in actual, current practice, lesssteam is required to thaw out a given volume of coal over the knownpractice previously above outlined.

In the present improvement, it is proposed to use the boiler, hose andsteam nozzle means heretofore used in current practice, but to introducemodifying structures and means therein, whereby to (1st), reduce theamount of thawing live steam used per given volume of frozen coal, (2nd)to create a fog like mist of high humidity as a means for betterdispersion of heat within and without the frozen coal body, 3rd) therebysaving steam and fuel, (4th) to apply the heated fog at a relatively lowpressure within the frozen coal thus to slow down its escape dischargefrom the pile, permitting the frozen coal to absorb more of the latentheat of the fog and finally, thawing the coal at a faster speed thanheretofore accomplished, thus effecting a further saving of fuel andsteam.

In one of the improved embodiments herein,

by providing a humidifier in the steam line from the boiler to thethawing nozzle, the introduction of sprayed Water into the live steamstream before its introduction into the frozen pile, causes theformation of what I call an artificial fog, wherein the humidity ormoisture content of the steam is increased to about 96%, and thepressure and temperature is correspondingly reduced, therefore due toreduced pressure the heated fog remains longer in the body of coal andmore completely passes its latent heat to the surrounding coal.

This artificial fog, when introduced into the coal pile, penetrates thefrozen coal more quickly than live steam, and more slowlyleaves thesame, and thus remains longer in the frozen coal because of its loss ofpressure by humidifying, .and the coal is quickly thawed out in lesstime than with live steam. The increase in efliciency, in time, amountsto about 40% to 60% over the high pressure live steam method, for agiven bulk of coal being treated.

In another form of thawing of coal in ton capacity coal cars, the carsmay be moved into an enclosing steam shed, and there treated in suchclosed sheds, thus conserving the heated, comminuted moisture whichforms the fog, as it leaves the interior of the coal in the cars;instead of letting it escape to waste in atmosphere as is now done inlive steam thawing, where the thawing is done in the open; and the coalis exteriorly surrounded by an outer, continuously circulated envelopeof heated fog and the frozen coal is thus attacked from within andwithout, simultaneously.

The foregoing and other features of advantage will be apprehended as theherein description proceeds, and it will be obvious that modificationsmay be made in the structures herein without departing from the spirithereof or the scope of the appended claims.

In the drawin Fig. 1 is a fragmentary partially sectioned view, inelevation of the present apparatus applied to a coal car for thawingpurposes;

Fig. 2 is a fragmentary, longitudinal view, in elevation, of a steam andwater mixing and atomizing humidifier nozzle structure;

Fig. 3 is an enlarged side view of a modified form of steam and watermixer nozzle;

Fig. 4 is a transverse sectional view, more or less diagrammatic showinga modified use of the present invention wherein the thawing of the caris done in an enclosing, closed steam or fog shed;

Fig. 5 is a more or less diagrammatic view in elevation showing therelative positions of the coal cars and the water atomizing means sprayand nozzles; and

Fig. 6 is a fragmentary longitudinal sectional view of thesteam andwater atomizer nozzle, which is identical with the atomizer head shownin my United States Patent #1,'I85,803, issued Dec. 23, 1930.

While the herein disclosure is directed to thawing frozen fuel such ascoal and coke, it is obvious that it may be utilized to thaw out otherfrozen materials such as sand, crushed ores and the like, and it is tobe understood that any reference to coal or fuel is inclusive of theseother materials.

The present system of thawing frozen coal comprises the use of a steamboiler generating plant, not shown, but well understood, steam beingconducted from said boiler through a valved connection 2, Fig. 1, into awater atomizer head I, said head being substantially a duplicate of thehead shown in Fig. 6, except as to outside dimensions of the foregoingnoted S. patent.

This head as shown in Fig. 6, herein, is so constructed as to receivesteam at one end which flows in the direction of the arrows A, to theconstricted medial Venturi ports in the direction of arrows E, being sodirected by cone D, where the steam stream traverses a plurality ofradially incoming water streams from a source of water supply, not showntraveling in the direction of the arrows F, towards the axis of thehead, the steam intercepting the water streams and heating and atomizingthe same and then both traveling as a heated mist or fog, in thedirection of the arrows E, to pass thence into the baflle plated mixingand expanding chamber 4, Fig. 1.

The incoming, radially directed jets of water which come directly fromsurrounding port l, impinge upon a curved impact seat G, which islocated upon the expanded perimeter of the cone D, and this aids, withthe dynamic flow of the steam stream, to atomize the water and to admixthe steam therewith.

As the fog mixture passes into the chamber 4, which may be cone shapedand which may be mounted upon a platform P, Fig. 1, it is interruptedand redirected by a cone shaped bafile 5 shown dotted in Fig. 1. Themixture then passes by the perimeter of the baffle to and throughcoupling valve connection or hand valve 8, to distributor pipe 5, andthence through couplings 9, and thence through flexible hose couplingIII, which latter is provided with steam point connectors V-V, by whichthe tubular steam point or fog nozzles II are operatively attached tosaid hose connection In and to the source of pressure fog supply 4. Thesupply of atomized water and steam may be supplied to chamber 4 so thatthe pressure of the contained fog may be maintained at about 40 to 50lbs., with or without the operation of the hand valve 8, which is mainlyused to shut off the fog when removing the steam points. The fog pointsI l, at their hose line connections or couplings are each provided withan anvil head H, whereby said points may be driven, by a hammer, intothe frozen coal, to the positions indicated in Fig. 1, wherein the car Chaving a load of coal 13 therein is shown as having a pair of steampoints embedded in the body of the coal. Any number of steam points andmixing chambers 4, may be used as a unit in a thawing operation as isindicated in Fig. 2. The steam points "-4 l, of Fig. 1, may be providedwith sharpened ends l6 and, with discharge slits l5 along theircylindrical surfaces, as in Fig. 3, whereby the fog may escape to thecoal.

In Fig. 3 there is shown an alternative form of nozzle, generallydenoted as 18, and which comprises a cylindrical fog discharge tubehaving a cone like end, an atomizer head I! being connected to theopposite end of the tube, which head has thereon an anvil head H, fordriving the sharpened tube l6 into the frozen coal, that portion of thepoint between its mid-section and point being provided with a pluralityof fog emitting slits I5.

This atomizer head may be constructed to mix steam and atomized waterinto a fog, as described for the device of Fig. 6, the head being servedby a. steam supply connection 2, and a water supply connection 3, tooperate as described for the atomizer head I, of Fig. 1.

In Fig. 4 there is shown an enclosed chamber 20, defined by surroundingwalls 2|, the opposite ends of the chamber being closed by doors, notshown, whereby car loads of coal C may be run into the chamber on thetracks 22, and the doors then closed, to retain the heated fog asgenerated.

Within the chamber and located over the cars is a main water distributorpipe 24, Figs. 4 and 5, and this pipe may be provided with a pluralityof water spraying heads 26, whereby water may be sprayed upon the coalin a fine mist. As in Fig. 4, the mist is traversed by an angular blastof live steam, which emits from live steam nozzle 21. The dynamic actionof these right angle discharged streams creates a vast quantity of verywarm foggy mist, the heat of which is gradually transferred to the coal.

On the track level, below the cars C, are arranged a plurality of pipelines 23, these being connected to a source of live steam, which passesthrough said pipes thereby causing them to act as a heating radiator forkeeping the thawing temperature constant within the chamber 20, forheating the thawing fog within said chamber and to prevent condensationof the fog therein. The fog acts as a capable heat circulating meanswithin the chamber 20.

In practice the water used for creating the fog, may be mixed, insuitable proportions, with dissolved deliquescent salts, such as calciumchloride, or chloride of sodium; sea water may be used as a fog makingaggregate with the steam. These added elements, over fresh water, tendto lower the freeze point of the water, and further hasten the thawingof the coal.

From the disclosure herein it is obvious that the low pressure steam andwater fog created as herein described, when distributed within the bulkof the frozen coal, disperses slowly through the bulk thereof andtransfers its latent heat slowly throughout the bulk, and does not thawout crater-like channels to atmosphere, as in current high pressuresteam practice, where the dispersion is slight, but its discharge toatmosphere is too rapid, after it cuts discharge vents in the bulk, anddischarges too much of its heat to atmosphere, without time to causeproper dispersion through the frozen bulk.

It is further obvious, that where loaded coal cars are, brought into thefog chamber or shed 2|, that the structure of Fig. 1 may be used to thawout interior of the frozen bulk fuel while the fuel is being thawed bythe surrounding fog within the shed, and which fog will be augmented bythe fog discharged from within the body of the coal. The heat from theradiator piping beneath the coal car also rises and directly attacks themore solidly frozen lower strata of frozen coal within the car.

What is claimed is:

1. A method of thawing weather exposed, frozen bulk coal, which consistsin commingling a dynamic stream of water and a dynamic stream of livesteam, thereby to create a fog, and directingthe fog into the body ofthe frozen bulk coal.

2. A method of thawing weather exposed, frozen bulk coal, which consistsin increasing the normal humidity of a high pressure stream of livesteam by introducing water into said stream to create a hot fog ofrelatively low pressure, and directing the hot fog into the body of thefrozen coal.

3. A method of thawing frozen bulk fuel which consists in subjecting thebulk fuel interiorly and exteriorly to a hot fog in a closed chamber.

4. A method of thawing frozen bulk fuel which consists in subjecting thebulk fuel exteriorly of its bulk to a hot fog in a closed chamber, andsimultaneously maintaining the temperature of the hot fog by heating thesame from a separate heat source.

5. A method of thawing frozen bulk fuel which consists in subjecting theinterior of the bulk fuel with a hot fog comprising commingled steam andatomized water at low pressure, the fog having a humidity of aboutninety percent.

6. The combination with an; apparatus for thawing frozen bulk coal,including a source of water and live steam supply, of a steam and wateratomizing head, a mixing, discharging and humidifying containerconnected to said head, a conduit connected to said container and aplurality of fog discharge nozzles connected to said conduit.

7. The combination with an apparatus for thawing frozen bulk fuel,including a source of water and live steam supply, of a bailied mixing,discharge and humidifying chamber, steam and water atomizing meansdischarging into said container, connections between said atomizingmeans and said steam and water source, means for separately regulatingsaid steam and water supply to said atomizer, a flexible conduitconnected to said discharge chamber, bulk insertible fog dischargingnozzles connected to said conduit and means for controlling the volumeof fog discharge therefrom.

8. The combination with an apparatus for thawing frozen bulk fuel,including a source of live steam and water supply, of an enclosed fogthawing chamber said chamber for cars with frozen bulk fuel therein, andlive steam and water atomizing and commingling nozzles therein forcreating a fog within said chamber to surround a car of frozen bulkfuel, to thaw the same.

9. The combination with an apparatus for thawing frozen bulk fuel,including a source of live steam and water supply, of an enclosed fogchamber for cars with frozen bulk fuel therein, live steam and wateratomizing and commingling nozzles connected to said supply sources forcreating a fuel thawing fog within said chamber and heat radiating meanswithin said chamber for maintaining sa-id fog at predetermined fuelthawing temperatures 10. In the art of thawing frozen bulk coal, amethod which comprises separately conducting to a mixing point water,and live steam having about 30 to 40 percent moisture; mixing said waterwith the steam at said point in a proportion to give to the mixtureabout 96 percent moisture; and introducing said mixture into theinterior of the bulk coal for thawing the bulk.

11. A method as in claim 10 comprising additionally heating the bulk byradiation during said thawing.

12. In the art of thawing frozen bulk coal, an apparatus which comprisesmeans for intimately mixing with a stream of live steam enough water toprovide a heavy fog, thereby to increase the thawing power of themixture; and means for delivering said mixture to the interior of thebulk coal for thawing the bulk.

-13. An apparatus as in claim 12 comprising means for supplyingadditional heat to said bulk during the thawing for retarding coolingand condensation of the fog and maintaining the efficiency and thawingpower of the fog.

14. Apparatus as in claim 12 comprising a heating means for supplyingadditional heat to the bulk during thawing, and means enclosing theheating means, the delivering means and said bulk to confine the heat ofthe fog and heating means to the bulk, and thereby effect saving of theheatof the fog and the heating means for increasing the efficiency ofthe heating thereof.

15. A method of thawing frozen bulk fuel in a closed-chamber, whichcomprises filling a large portion of saidchamberexterior to the coalwith hot fog; and subjecting bulk fuel in said chamber sufficiently tosaid hot fog to effectively thaw the coal.

16. A method as in claim 15 in which the fog is heated from a separatesource of heat.

17. A method comprising exposing frozen broken bulk fuel in a closedchamber filled to hot fog, hot enough and sufficient in quantity toeffectively thaw the coal.

18. A method as in claim 17 comprising heating said hot fog from aseparate source of heat.

19. In the art of thawing frozen bulk coal, a method which comprisesseparately conducting water and live steam to a mixing point; mixingsaid water with the steam at said point to form a hot fog and applyingsaid fog to the bulk coal in sufficient quantity to effectively thaw thebulk.

20. A method as in claim 19 comprising additionally heating the bulk byradiation during said thawing.

21. In the art of thawing frozen bulk coal, a method which comprisesseparately conducting to a mixing point, water and live steam; mixingsaid water with the steam at said point in a proportion to give to themixture increased moisture; and introducing said mixture to the interiorof the bulk coal for thawing the bulk.

22. In the art or thawing frozen bulk coal, a method which comprisesintroducing to the interior oi the bulk coal a hot fogcontaining about96 percent moisture, for thawing the bulk.

23. A method as in claim 22 comprising additionally heating the bulk byradiation during said thawing. I

24. In a fog generating means, the combination of a fog generating headhaving a discharge opening; means for supplying water and steam intosaid head and therein atomizing and mixing them and discharging theatomized mixture at said discharge opening; a large humidifying chamberhaving a discharge end, and a wall across its other end provided with anopening in register with said discharge opening; and a bafiie acrosssaid chamber spaced irom the side walls end, and a wall across its largeend provided with 10 a' central opening and secured with said centralopening in register with said discharge opening, the discharge openingdischarging into the chamber; and a cone shaped baille in said chambercoaxial with the chamber and said openings and 15 spaced from the sidewalls of the chamber and pointing toward said openings.

HENRY ADAMS.

